As a cleaning agent for cleaning a molding processing machine of a thermoplastic resin composition, there is known one obtained by combining a base resin and other components.
In JP-A 2010-95624, JP-A 2010-95625, JP-A 2011-46808, JP-A 10-279816, and JP-A 2007-21765, there are disclosed cleaning compositions in which a base resin and an anionic surfactant are combined.